LÖNNBERG, THE PELVIC BONES OF SOME CETACEA. 



ilium. The distal end of the femur is also surrounded by a 

 cartilaginous layer but this is much thinner than the proxi- 

 mal. Beyond this distal cartilage of the femur the fibrons 

 tissue begins again and unites with the end of the femur a 

 cartilaginous body which I regret to say is nearly cut away 

 on the left side and badly mutilated on the right. The latter 

 has, however, still a length of about 12 cm. but how much 

 longer it has been, is impossible 



to say. It represents certainly 

 the rudiment of a tibia. Its 

 thickness proximally is between 

 3 and 4 cm. 



yf4'//-'i-,^ 



Fig. 4. The acetabvi- 



lar cavity of the femur 



of Balcena austraLis. 



Fig. 5. A section through the 



connection between femur and 



pel vis of Balcena australis. 



Thanks to the description and figures communicated by 

 Abel in his memoir^ on »die Morphologie der Hiiftbeinrudi- 

 mente der Cetaceen» a comparison can be made between these 

 pelvic rudiments just described and those of the Nordcaper 

 (Balcena glacialis). The pelvic bones of the latter described 

 by Abel have belonged to a specimen measuring 16 m. in 

 length but nevertheless they are very much smaller as is 

 most easily seen if the resp. figures are put side by side 



